摘要 |
<p>Waste paper is recovered by coarse pulping in a pulper, preliminary sorting, thickening to stock densities of more than 10%, treatment in a reaction tower in the presence of de-inking chemicals followed by thinning of the suspension and flotation in a flotation appliance. The invention is characterised in that at least some of the de-inking chemicals are introduced in the pulper, and in that the water laden with particles of printing ink which is yielded during the thickening process before the reaction tower is subjected to flotation in a subsidiary circuit flotation appliance clean water obtained from this appliance being reintroduced into the process. As a further development, the froth arising from the flotation appliance is introduced into the subsidiary circuit flotation appliance for after-treatment.</p> |